Tambour-frame-counterbalancing mechanism.



R. ZAHN, DBGD.

A. mm'zson, ADMINISTRATOR.

TAMBOUR FRAME COUNTERBALANGING MECHANISM.

APPLICATION FILED IBB. 9,1914.

4 572 7 Patented Jan. 12, 1915.

THE NORRIS PETERS 60.. PHOTO-LITHDV, WASHING TON. D. c.

UNlTED STA E ATENT QFlFlQEQ ROBERT ZAHN, DECEASED, BY ALFRED RIETZSCH, ADMINISTRATOR, OF PLAUEN,

. GEEMIANY.

TAMBOUR-FRAME-COUNTERBALANCING MECHANISM.

Application filed February 9, 1914.

T 0 all 117101/0 it may concern Be it known that l, ALFRED Rmrzscn, a subject of the German Emperor, and a resident of Plauen, in Vogtland, in the Kingtor of the estate of Ronmrr ZAHN, deceased, who was a subject of the German Emperor, and that said ROBERT ZAHN has invented the new and useful Improvement in Tambour-Frame-Colinterbalancing Mechanism, of which the annexed is a specification.

The precision with which the tambour frame in embroidering machines moves depends entirely upon the manner in which it is suspended and also upon the distribution of the sluggish masses. With the substitution of the springs for heavy counterbalancing weights, a new problem is presented in the construction of embroidering machines, namely that of so distributing the spring forces that their actions during the movements of the tambour frame be perfectly uniform. As long as counterweights were employed counter-balancing was very simple in so far as the gravity of the counterweights was transferred by suitable rigid means to the two remotest points of the tambour frame at the right and left ends thereof. The same method could be adopted when counter-balancing is effected by springs, but the nature of springs requires that the spring forces themselves he properlv divided and applied in the machine directlv to the points at which they are to act. In that case it would be merely necessary to employ a proper intermediate mechanism, so as to render the movement at both ends of the tambour frame absolutely uniform.

In order that the progress made in the embroidering machine art afforded bv the present invention may be fullv appreciated, it is necessarv to bear in m nd the different actions of the two counter-balancing svsterns. to-wit: on one hand that of counterweights and on the other hand that of springs. -With counterweight counterbalancing it is immaterial whether a single large counterweight or two weights of half the size are used. the inertia. of the tambour frame and that of the counterweights will always counteract one another and thereby cause an alternate drag in one and the other direction on the stationary masses of the machine frame. This alternate action is ob Specification of Letters Patent.

0.0111 of Saxony, Germany, am administra-v Patented Jan. 12, 1915. Serial No. 817,497. I

viated with spring counterbalancing not only because one half of the sluggish masses,

namely that of the counterweights, is entirely done away with, but principally be cause there are no more sluggish masses that could counteract one another. If the right half of the tambour frame is ust as heavy as the left half, which ordinarily will be the case, and if both ends of the tambour frame are counterbalanced by uniform springs, then the only cause that gave rise to jerks, ars, etc, has been completely removed.

My invention will be more fully understood by reference to the accompanying drawing, in which similar reference characters denote corresponding parts and in which- Figure 1 is an elevation of an embroidering machine having my new tambour frame suspension and counter-balancing device and Fig. 2 is an end view of the suspension and counterbalancing device.

ln the drawing, which forms part of this specification. 1 denotes the stationary machine frame and 2 the jacquard mechanism for controlling the movements of the tambour frame. The movable tambour frame 3 has the usual lateral brackets or rails 3' whereby it is adapted to be suspended in a floating manner in the machine frame so that the same may receive universal movements in a vertical plane in order that all operations required for producing embroidery work can he easily accomplished. At each end and at a high point the machine frame is provided with brackets 4 in which are borne rotary shafts 5 and 6, arranged parallel and alcove one another.

Since the suspension and counterbalancing mechanisms at both ends of the machine are identical in structure and operation, I shall describe in detail only one of them, it being understood that the description applies to both. Loose on the spindle 5 is a gear 7 and fixed on said shaft is a cam disk 8. A coil spring 10 is connected with one end to the ratchet gear 7 and at the other end to the disk 8, the gear serving for the adiustment of the tension of the spring. Keyed on the spindle 6 is a cam disk 8. which is arranged in a vertical plane with the cam 8 and is connected to the latter by a steel band 9, mounted around and fastened to their circumferences. The two cams cooperating together in Wll knownmanner are adapted to afford uniform acwhich is fixed a steel band 12, the other end of which is connected to a steel band 13 which is guided over a pulley 14 suitably supported in a stationary part of the machine and Which band it With its free end carries a forked-shaped member 15. This latter is vertically guided upon stationary vertical rods 1 6,and carries a roller 17 The tambour frame 3 rests With its lateral arms 3" on the rollers 17, of the members 15. Supported on the shaft 6, are pulleys 18 connected by an endless steel bandlS), which serves for the transmissionof synchronous movement from one pulley to the other. It Will be seen that by this arrangement the tambour. frame is perfectly counterbalanced. The band 19 may be guided over guide rollers 20 supported in brackets 21 fixed to the frame,

What I claim, and; desire to; secure LettersPatent is p p 1. In an embroidering, machine, a tam? bour frame, a tambour frame suspension and counterbalancing mechanism, comprismg a spring at each end of said: tambour frame, hangers acted upon by said springs and carrying the 'tambourframe, a'rotary;

Copies of this patent maybe obtained for necting said shafts and securing synchro- I shaft at each end of the tambour frame each shaft being acted upon by the corresponding spring, spring compensating means interposed betWeen sa d shafts and springs, and

a band or Wire connecting said shafts and securingsynchronous movement thereof.

3. In an embroidering machine, a stationary frame, a tambour frame, a tambour frame suspension and 'counterbalancing mechanism, comprlsmg a sprmg at each end of said tambour frame, hangers acted uponby said springs and carrying the tambour frame,a rotary shaft supported at a high point on the stationary frame and arranged at each end of the tambour frame, said shafts being acted upon by said springs, and a band or Wire eonnecting' said' shafts and securing synchronous movement thereof.

In testimony whereof I afiix my, signature in presence of two Witnesses.

ALFRED RIETZSCH, Administrator of, the'estate of Robert Zaim,

deceased.- lVitnesses: Josnr GRoMz, Bonner H. NIER,

five cents each, by addressing the Commissioner of Patents,

Washington, D. G. 

